<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Document</title>
    <!-- <script src="http://localhost:8080"></script> -->
    <!-- 引入react核心库 -->
    <script type="text/javascript" src="../../js/react.development.js"></script>
    <!-- 用于支持react操作DOM -->
    <script type="text/javascript" src="../../js/react-dom.development.js"></script>
    <!-- 用于将jsx转为js -->
    <script type="text/javascript" src="../../js/babel.min.js"></script>
</head>
<body>
    <button id="btn1">按钮1</button>
    <button id="btn2">按钮2</button>
    <button onclick="show()">按钮3</button>

    <script type="text/javascript">
        // 方法1 
        const btn1 = document.getElementById("btn1")
        btn1.addEventListener("click", () => {
            alert("按钮1被点击")
        })
        // 方法2
        const btn2 = document.getElementById("btn2")
        btn2.onclick = () => {
            alert("按钮2被点击")
        }
        // 方法3
        function show(){
            alert("按钮3被点击")
        }
    </script>
</body>
<style>
</style>
</html>